The present invention relates to portable sound systems which are used in connection with headphones and especially to a sound recognition and interrupt system for disengaging the connection between the sound source and the headphone.
The popularity of portable sound systems, such as portable CD players and portable cassette players, connected to headphones, has reached an ever expanding market. Portable stereo systems used in connection with headphones have been used by runners and joggers as well as by walkers and people traveling in cars and flying in airplanes. One of the problems encountered in the wide usage of such headphone stereo systems is that while the listener has the headphones on, he cannot hear extraneous noises, such as sirens or emergency warning devices. When a person has earphones in place over the ears with the sound system playing loud music or the like, extraneous sound signals are completely obliterated. The signals thus become a hazard to the user of the headphones in the case of emergency or warning signals and are inconvenient when anyone desires to communicate with a person using the headphone stereo system. The headphone wearer, in effect, is tuned out to loud from all extraneous noises and communications.
It has been suggested in the past to pick up extraneous sounds, especially in automobiles and vehicles, and recreate the sounds within the vehicle cab, either over the radio or to interrupt the radio and produce the sounds. This becomes important within vehicles since persons driving with the windows up and a radio playing are unable to hear sirens or emergency vehicles, which may be result in endangering people's lives. The problem is aggravated by portable stereo systems worn by people driving cars or in vehicles since, even if the radio is turned down and a warning is made within the vehicle, the wearer of the headphones would not hear the extraneous sounds.
The present invention is directed towards a simplified system that can be attached to a belt of a person with headphones and listening to a sound system. Both the headphones and the sound system are plugged into the belt unit which can detect extraneous sounds of a predetermined level to switch off the sound system and to amplify the extraneous sounds, if desired, and then to allow the user to switch the sound system back on manually when he had heard the extraneous sounds.
There have been a number of systems which use voice actuated switches in connection with intercom systems to switch off a stereo audio system. A person's voice actuates the intercom and then switches the stereo system back on. This type of system, for instance, has been suggested especially for motorcycle drivers having a passenger, both of which can be connected to an intercom system. In the Stafford et al. U.S. Pat. No. 4,754,486, a motorcycle stereo audio system with vox intercom is provided to allow intercom communication between the motorcycle driver and a passenger while providing stereo listening in both the right and left helmet earphones and intercom communication through microphones which are always actuated and located proximate to the mouth of both driver and passenger. In the Bayer U.S. Pat. No. 4,006,310, a noise discriminating voice switched two-way intercom system is provided for remote banking which facilitates communication between a teller terminal and a remotely located customer terminal. In the Stafford et al. U.S. Pat. No. 5,243,659, another motorcycle stereo audio system with vox intercom is provided such that initial speaking in the microphone terminates the stereo output of both right and left speakers of the driver and passenger helmets so that the intercom conversation is heard in full. In the Chapple U.S. Pat. No. 4,881, 123, an audio system has a voice override and voice amplification control circuitry to provide high quality music to a listener through a set of headphones and includes a microphone and a foot operated switch to allow a user to override the music signal to communicate with the listener.
In the Hochstein U.S. Pat. No. 4,975,964, an automatic turn off system senses the presence of electrical signals for use in a wireless audio speaker system for turning off the speaker system in the absence of the audio signal. In the Simpson U.S. Pat. No. 3,280,272, a muting switch mechanism for an automatic record changer is provided for preventing the noise created by the record changing mechanism from being amplified and transmitted through the speaker system. The Schorman et al. U.S. Pat. No. 5,054,078, is a method and apparatus to suspend so that a person listening to a radio in a noisy environment, such as an automobile, who might normally miss some of the received speech when the noise occurs, such as a horn honking or a door being slammed or a person in the car speaks. In such case, the radio user may have to ask the person at the other end to repeat the message. This system provides a storage buffer to store information that might otherwise be lost. In the Hawkins U.S. Pat. No. 3, 518,375, a voice override circuit is provided in which a voice signal from a microphone automatically suppresses a normal music signal and resumes after the voice signal terminates. In the Fricke et al. U.S. Pat. No. 4,061,874, a system for reproducing sound information controls a car radio or the like playing in traffic or engine noise by controlling the volume in dynamic range of the audio amplifier using an ambient acoustic noise sensor. In the Fox U.S. Pat. No. 4,455,677, a multipurpose headphone assembly is used in connection with a stereophonic system and detects noises extraneous to the stereophonic output system using a pickup microphone and one or more speaker assemblies for ambient sound pickup. The pickup microphone is connected to an automatically actuated switch which closes whenever the pickup microphone detects certain ambient sounds extraneous to the system. The automated switch assembly is directly interconnected with a voice compressor assembly and then directly to an amplifier to provide minimal amplification of such extraneous sounds.
In contrast to the prior systems, the present system is a self-contained unit for attaching to the belt of an individual or to his clothing or body and which allows for the headphones to be plugged thereinto with the CD player or cassette player plugged thereinto so that the sound from the sound source to the headphones can be interrupted subject to predetermined sound levels being picked up by a microphone in the housing to switch off the connection between the sound source and the earphone, which connection is manually reset at the option of the user. Extraneous sounds can also be processed as desired.